Comparison of ANI Between Preoperative and Postoperative Ultrasound-guided TAP Block in Laparoscopic Cholecystectomy

NCT07809009 | Not Yet Recruiting

• 1 other identifier: 11-2026-023
• Study Type: interventional
• Target: 120
• Locations: 0 countries
• Sites: N/A

Brief Summary

The goal of this clinical trial is to learn if the timing of ultrasound-guided transversus abdominis plane block (US-TAP block) administration (preoperative vs. postoperative) affects the perioperative analgesia nociception index (ANI) in adult patients undergoing laparoscopic cholecystectomy. The main questions it aims to answer are:

• Does the timing of the US-TAP block significantly influence intraoperative ANI values?
• Does the difference in US-TAP block timing and subsequent ANI values correlate with actual patient recovery, postoperative pain scores (VAS), and complication rates? If there is a comparison group: Researchers will compare the experimental group (Group A: US-TAP block before surgical incision) to the control group (Group B: US-TAP block after wound closure) to see if early block administration provides superior intraoperative pain suppression and reduces postoperative pain or analgesic consumption. Participants will:
• Undergo standard general anesthesia induction and maintenance.
• Receive a bilateral US-TAP block with a total of 30 mL of 0.2% ropivacaine, administered either before incision (Group A) or after closure (Group B).
• Be monitored via standard monitoring devices alongside an ANI monitor.
• Use an intravenous patient-controlled analgesia (IV-PCA) pump for 24 hours after surgery.
• Participate in postoperative assessments to measure pain scores (VAS), rescue analgesic consumption, satisfaction, and complications at specific intervals up to 24 hours post-surgery.

Conditions

Laparoscopic Cholecystectomy; Postoperative Pain

Outcome Measures

Primary Outcomes (1)

• Intraoperative Analgesia Nociception Index (ANI)

  From anesthesia induction until the end of surgery (approximately 1-2 hours)

Secondary Outcomes (4)

• Postoperative Pain Intensity via Visual Analogue Scale (VAS)

  Up to 24 hours post-surgery (Specifically measured at: upon arrival at the PACU, immediately before PACU discharge, and at 12 and 24 hours post-surgery)

• Cumulative Postoperative Rescue Analgesic Consumption

  From the end of surgery up to 24 hours post-surgery

• Incidence of Postoperative Complications and Adverse Events

  From the end of surgery up to 24 hours post-surgery

• Patient Satisfaction Score for Postoperative Pain Management

  At 24 hours post-surgery

Study Arms (2)

Group A: Preoperative US-TAP Block

EXPERIMENTAL

Patients receiving ultrasound-guided transversus abdominis plane block immediately after general anesthesia induction, prior to surgical incision.

Procedure: Preoperative US-TAP Block

Group B: Postoperative US-TAP Block

ACTIVE COMPARATOR

Patients receiving ultrasound-guided transversus abdominis plane block after surgical wound closure is completed, before discontinuing inhalation anesthetics.

Procedure: Postoperative US-TAP Block

Interventions

Preoperative US-TAP Block PROCEDURE

Ultrasound-guided transversus abdominis plane block administered immediately after general anesthesia induction, prior to surgical incision, using 0.2% ropivacaine (total 30 mL).

Group A: Preoperative US-TAP Block

Postoperative US-TAP Block PROCEDURE

Ultrasound-guided transversus abdominis plane block administered after surgical wound closure is completed, before discontinuing inhalation anesthetics, using 0.2% ropivacaine (total 30 mL).

Group B: Postoperative US-TAP Block

Eligibility Criteria

• Age: 19 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Patients scheduled to undergo laparoscopic cholecystectomy.
• Aged 19 years or older.
• American Society of Anesthesiologists (ASA) physical status I, II, or III.

You may not qualify if:

• Patients who lack the capacity to understand the study examinations or perform the assessment procedures.
• Patients with coagulation deficiencies or bleeding disorders.
• Patients with cardiac arrhythmias or those with an implanted cardiac pacemaker.
• Patients taking medications that affect the autonomic nervous system, including beta-blockers and opioid analgesics.
• Patients with surgical scars, active lesions, or anatomical abnormalities at the block site.
• Patients with pre-existing neurological deficits or impairment at the block site.
• Patients with a known history of allergic reactions or hypersensitivity to ropivacaine or other local anesthetics.
• Pregnant or lactating individuals.

Sponsors & Collaborators

• Pusan National University Yangsan Hospital: lead

MeSH Terms

Conditions

Pain, Postoperative

Condition Hierarchy (Ancestors)

Postoperative Complications; Pathologic Processes; Pathological Conditions, Signs and Symptoms; Pain; Neurologic Manifestations; Signs and Symptoms

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Professor, Department of Anesthesiology and Pain Medicine

Study Record Dates

• First Submitted: September 2, 2026
• First Posted: September 9, 2026
• Study Start: August 31, 2026
• Primary Completion (Estimated): June 30, 2027
• Study Completion (Estimated): June 30, 2027
• Last Updated: September 9, 2026

Record last verified: 2026-09

Data Sharing

• IPD Sharing: Will not share